Delayed self-closing gas valve



Feb. 6, 1923. 1,444,011

R. D. SMITH.

DELAYED SELF CLOSING GAs VALVE. Omcmm. FILED APR. 27, 1917. 2 SHEETS'SHEET I 35 i i ame mm, 39 ERWWMQlfiW ikh Patented Feb. 6, 1923.

warren stares ear-E Nr oFFIo-e.

RAYMOND D. sivnrn, on new MILTON, nassacnusnrrsgassrenon ro SHAWMUT MACHINE WORKS, Inc, a conronarron or MAINE.

DELAYED SELF-CLOSING Gas vA vn,

A plication filed April 27, 1917, Serial No. 165,026. Renewed July 8, 1922. Serial No. 573,631;

To cZZ LU 710m it may concern Be it known that I, RAYMOND D. SMITH, a citizen of the United States, residing at East Milton, in the county of Norfolk and Commonwealth of Massachusetts, have invented certain nevv and useful Improvements in Delayed Self-Closing Gas Valves, of which the following is a specification.

This invention relates to mechanism for eifecting the delayed automatic closure ofcommonly used to control the gas supply to the burner of a small gas watenheater.

The invention has for its general object to provide in compact and self-contained form an ordinary and approved type of gas valve and mechanism for operating the same, so associated therewith, that the valve is thereby rendered manually adjustable as usual to any desired degree of opening, and such mechanism further incorporating automatic means energizable at Will, by manipulation of the usual valve controlling extension, whereby automatic closure .of the valve, after a substantial period of delay, may be had throughcontrolled thermo-dynamic effects;and preferably through automatic government and utilization of'the gas supply to produce the heat effects necessary in securing the designed thermostatic action, all as consequent. upon simple actuation of the manual valve turning means.

In practice, such delayed closure of the valve may take place, to advantage, after an interval of time varying, say, from live to thirty minutes after energization of the automatic means above referred to," such timeinterval being readily alterable by varying certain elements of the device. The very material convenience in operation offered by my improved gas valve when used in the connection above referred to is obviously that the operator is enabled to set the valve for delayed closure and go, about other business without having to remain, or to return, to shut off the gas at the proper time.

In the provision of a valve having the characteristics above dQSCIlbBCl and of an operating mechanism therefor which shall be at once simple, durable and nexpensive to produce, a'pa-rticular ob ect ef-the present invention is to utilizethe principles of heat transmlssion to produce the desired lntervalof time. in the automatic operation of the valve, for, by such principles',;a delayed automatic valve action can be governed by aslight mechanical movement caused .by the slow accumulation of heat in some simple thermo-dynamic element, suchas a fluidiilled thermostat, rather than by some comparatively complex, and mechanically retarded, motive "device such as a springdriv'en clock movement or the like, as is customarily employed for this purpose.

As .I have filed other applications for U. S. Letters Patent for thermostatic valvecontrolling mechanism of somewhat similar character, I will here point out some ofthe novel features distinguishing the present improvement from the structures and principles'of operation disclosedin said other applications. In a preferred form the present arrangement involves (as do certain of my otherapplications) thezuse of a main and auxiliary burner, co -operatively acting in controlling automatic extinguishment of the said main burner; but for separately governing thesupply of gas'respectively to each of said two burners, two separate valves are.

herein provided-both adapted to be actuacted in predetermined operative relation by a single radially extending control arm which in the'speciflc embodiment herein disclosed is spring-connected to the main valve totension the same for automatic closure. In connection With this control arm, Ihave herein provideda novel form ofmanually releasable latch device for locking said arm in a position to establish the valve-closing.

tension, and a new function herein given to such latch device is that of serving as a trigger for conveniently tripping the thermostatically governed detent thereby to free the main valve from restraint by the latter to permit undelayed valve closurethrough direct manipulation of the control arm.

Also'novel in the present improvement is the use of a liquid-filled thermostatic disc for governing the valve detaining detent,-a laminated or flexing band type of thermostat having, heretofore been employed for this purpose. The disc form of'thermostat,

in generalpis 7 capable of performing more movementand of exerting greater force than a band thermostat, but its incorporation within a compactly organized mechanism presents severa-l structura-l problems that are effectively solved by the detailsci' arrange-- ment hereinafter described.

A particular mechanical feature oi my improved valve controlling mechanism, and one that constitutes an important object of the presentinvention. resides in a novelly ar ranged detent, which virtually constitutes an indirect-lock for the valveywherehy the latter may be retained in an open position againstpowerful tension tending. to close the-same, and yet" is adapted to be automati cally release d. for closure by comparatively a very weal:thermostatic .e'liort. It has developed in practice that the friction between engaging detentsuriaces, which results from direct opposition by a thermostatically operated detent.member to the powerful valve-closing spring,- imposes too great a load upon the preferred type of thermostat to enable the'latter satisfactorily to trip such detent member. Thenovell arranged dc tent,.above referred to, provides in compact and rugged form a simple and cliective remedy for this condition, and the novel principles of the arrangement may be applied to equal advantage in apparatus that employs as the detent-tripping agent a clocl-i mechanism or other timer device that is ca pable of exerting only a comparatively weak force.

Other and specific objects of the invention reside inthe provisionof novelly arranged and novelly control-led auxiliary burner for generating the heat to be accumula-ted by the thermostat, in the means For causing the automatic ignition of this auxiliary burner from the flame of the main waterheater burner, and in various details of construction aimed generally to conserovate the heat generated by the auxiliary burner andto protect the designed heat paths from operative disturbance by outside temperature conditions.

To the accomplishment of the above described objects among; others hereinafter to be pointed out, my inventionresides in several diiferent combinations and arrangements of elements, a. preferred form of which, for illustrative purposes only, is next to be described. reference being had to the accompanying; drawings in which Fig. l is a front view-in elevation showing my improved delayed closing valve in open position with certain associated burner parts. including the base of a Q'asand-air "mixing" chamber for the'gas-water heater ibu-rner, ithe wall thereof and also certain other. parts being partially broken away-or shown insection forclearncss; Fig. 2 is a .SlClQ view in-elevation looking at the left of Fig. 1- .and showing the mechanism casing :in section, portion'of the thermostat heat conductor being broken away; Fig. 3 is a view similar to Fig. 1 showing the positions of parts when the valve is closed Fig. 4 is also a view similar to Fig. 1, with the valve tensioned for closure but held open by the thermostatically governed detent latch; Fig. 5 shows a modification in'the construction ductor and auxiliary burner parts, whereby certain useful purposes are served; Fig. 6 is a front elevation of the valve with the. modification above mentioned part of the heat chamber wall being broken away more clearly to show the interior parts; Fig. 7 is an assembly view on a reduced scale showing the valve and water heater burner in which view the position of the auxiliaryburner relative to the latter, and also the arrangen'ient for causing automatic ignition of said auxiliary burner are clearly shown; Fig. 8 is a sectional view through the centre of the thermostat on the plane 88 in Fig. 2, she-wing the method of supporting the same.

Throughout the several views of the drawings identical parts are designated by similar reference numerals.

A. valve body is shown at 10 with suitably threaded terminals 11 for connecting the same in the pipe line between the supply and the controlled water-heater burner 71, as shown in Fig. 7, only the base 9 of a mixing chamber for the and air delivered to the latter appeariin the other views. The

' usual rotative tapered valve plug 12 is held axially in its seat in said body by the spring 13 as usual, and. oscillates therein to control the flow of gas by varying the rotative-position of the diametrica-l opening 14- through the plug. In Figs; 1 and 4. this opening is positioned in alignment with the gas passage 15 in the valve body 10, so that the valve is open.

A dogpla e 16, having; a hub 31. is rigidly pinned to the forward end oi a stem 11? of the valve plug; 12, which latter is turned down at this portion to a constant diameter and carries loosely pivoted thereon, between the dog-plate 16, and the valve body 10, the hub 18 .oif'a control lever 19.providcd at one end with handle 20. At the opposite end,

and arrangement oi the thermostat heat con this control lever is provided. with a rearwardly extending terminal 61 for purposes to be later described. spiralleaf spring; 21 at one end thereof is secured to the hub 18 and at the other end 23 to a rearward extension 24c of the dog-plate 16, so as normally to hold said extension andthe con trol lever 19 in engagement and thereby the plug 12 and the control lever 19 in definite rotati-ve relation, but separable therefrom against tension in-spring; 21 in one relative direction of rotation' Frame lugs 64; 64v limit the-swingof the lever 19.

The, control lever 19 carries pivoted thereto at 3, a combined latch and trigger mem ber formed as a three-armed lever and l normally positioned by the spring 26 to engage at a catchformed end 27 of the down wardly disposed arm 4:0, with a stationary lock stud 28 projecting forwardly from the valve body, thereby to lock the control lever 19 in its position shown in Figs. 3 and Another of these arms ll extends outwardlysubstantially in radial alignment with the control arm 19 and terminates in forwardly extending portion 43 near the handle 20 to be conveniently operated in conjunction therewith for purposes hereinafter de': scribed. The third arm 42 is disposed oppositely the arm 46 and is operative as'a trigger only in the position of the control.

arm 19 shown in Fig. 1 and for purposes to at its free end 6 extends rearwardly to be.

engaged in a certain position of the clogplate and when the strut arm 30 is in contact with the roller 37, by a detent latch arm at the catch formed end 32 of the latter. The latch arm 35 has a hub portion 44 which carries also an upwardly extending trip arm 45, and pivoted to the end of the latter is a 1 floating trip bar 46 adapted at its free end to be engaged at certain times by the arm- 42 of the lever for tripping the detent arm as shown in Fig. 1. The hub 4A is secured by suitable, and preferably by 'rotatively' adjustable means (such as a set screw). to a horizontally disposed shaft 47 formed at one portion 48 thereof as a crank and journaled at its ends in a side support bracket a9 and in the bracket extension 39 respectively. At its point of greatest eccentricity the said crank portion 48 of-the shaft a7 is caused to bear upon the centre of a disc thermostat 50 by the torsional tension in a'spring 51 coiled about the shaft 47, and the latch lever is thus positioned, when the thermostat 50 is normally cool,v to intercept the strut arm 30 as shown in Fig. 4.

The-disc thermostat 50, as shown, com

prises two expansible and annularly corrugated. metallic discs, sealed gas tight at their periphery and filled to suitable capacity with a thermally expansible fluid. Radially disposed ribs 52, secured at their ends by U- shaped clips 63. and having a central threaded boss 75, serve as a convenient me ans for mounting the thermostat by means of a screw 76 on some suitable thermally conductive metallic member, such-as theupwardly extending bar 53 as shownin Fig. 8,

. bar 'being preferably of' appreciable ..-ngth for retarding the "deliverance of.

heat to the thermostat. A

inclusive, the bar 53 is shown as extending upwardly and terminatingin an inwardly disposed, upright, hollow cone 5e, open at the bottom and provided with a small perfoin vertical alignment rat-ion at its top. I with the "cone, and beneath the-same, 1s an upright Bunsen burner tube 56w1th open- In Figs. 1 to 1-,-

ings' STfor the air supply theretmthe said u burner aving; a gassupply tapped from the. main valve body gas passage 15 a lateral outlet 58 therefrom, the said supply being controlled by a gas cock 59, arranged between said outlet and the Bunsen burner tube 56, and said cock being provided with a'twofingered operating cam 60 therefor. The cam 60 and thereby the cock 59 is adapted. to beoperatively engaged by the extremity 61 of the control lever 19heretoforedescribed. y

It will be noted in Figs. 1 and 2 that the heat conducting bar 53 is not secured in direct contact-with the side frame-plate49 but s spaced, therefrom. by heat resistive blISllll'lQS and washers, such'as. shown at 62 in the said figure. so that heat tra ns initted from the flame of the'Bunsen tube to the" thermostat by the bar 53cannot readily escape from the latter to the supporting structure therefon I I I f In Figs. 5 and 6, the auxiliary burner and heat conductive means are shown in modiform, the said burner herecomprising minating' burner tube 65 above the open end of which falls the heat receiving end 66 of amodified form of heat conducting bar=67 to which latter thethermostat 50 is secured as usual. The heat receiving: end 66 is domeshaped and has an opening}- 68 positioned di a downwardlyextending and upwardly terrectly over the said 'end of the burner tube i 65. "All of the parts above described'are contained in a substantially closed chamber,

having sufiicientvent to support combustion of the small burner flame, and also having transparent window'69 .of'some suitable material, such as mica, to render visible the flame. I

T In the above described modlfied structure the transmission and accumulative effect of the heat is obviouslyless susceptibleto' drafts or surroundi 11;; outside temperature conditions; and operation'of the device is rendered therefore more reliable under extremely cold or drafty conditions. It will be appreciated that'this modifiedconstruo,

tion embodies practically an oven with" an internal source of heat, and I preferably introduce heat insulation between such oven and the rest of the structure, so that the lat ter may not be undulyv he'ated during theinter-val of time designed in effectingthe delayed-operation of the device. I may. better ments forgenerating and controlling the heat used to operate the thermostat, the auxiliary burner (when supplied with gas) is adapted to be automaticallyignited; by

thenatural rise of such gas through a suit-' able and unobstructed conduit therefor, as is provided by the tube 70 in Fig. 5, the said tube terminating adjacent and preferably below some point of maximum heat of the flame of the main burner 71 so as to deliver the said gas thereto. When thus ignited, the flame flashes backwardly through the tube and subsequentlyburns at the mouth of the auxiliary burner to supply heat for op--I crating the thermostat. Also in each of the described arrangements, adjustment of the size of the auxiliary burner-flame may be had by the screw'72. V

A casing73 is provided to house the parts and a wing nut 74: is secured to the end of the valve stem exterior of such casing to indicate the true position of the valve and to act as positive means for operating the valve in case the automatic control mechanism goes wrong.

The operation of the valve and controlling mechanism above describedis as follows: Starting from a position of parts as in Fig. 1 where the valve is open and the main waterheater burner not shown in this figure) is assumed to be ignited and in normal operation, the'valve maybe partially or wholly closed by manually depressing the handle to swing the lever 19 toward its position in Fig. 3. At the beginning of such depression, however, the end 43 of lever must be pressed upwardly toward the handle 20, which act may-be conveniently performed by the fore-finger of the operators hand, to

trip the latch arm 35, which otherwise retains the strut arm and thereby the valve dog 16 in valve-opening position. Upon arrival of the control lever 19 at its position as in Fig. 3, it will be locked therein by latching engagement of the arm with the stud 28, and must be releasedfrom such engagement by manipulation of the lever 25 similar to that above described before the valve can again be opened.

To produce delayed closure of the valve, from its open position as shown in Fig. 1, the handle 20 is depressed as said, but without tripping the detent latch arm 35, whereupon the valve is retained open by the latter and the spring "31 is established under ten sion tending to. close the valve. This position of parts is shown in Fig. l, and from this figure it will be apparent that the end 61 of control lever 19 has operated cam is effected.

to, open the cook 59 and supply gas to the auxiliary burner. Such burner thereupon ignites automatically from the heat of the main water-heater burner as heretofore described and operates to transmit heat slowly to the thermostat through the heat conducting bar 53 therefor. The interval of time required to raise the thermostat to its designed operative temperature constitutes the delay before automatic closure of the valve Such closure is caused by the spring 21' when the thermostat has been axially expanded by the heat sufficiently to retract the latch arm 35 from restraining engagement with the end 6 of the strut arm 30, thereby freeing the valve dog 16.

The nature of the indirect lock provided by the co-operative arrangement of the strut arm 30, the detent latch 35 and'the' roller abutment 37 is such that the greater part of the powerful valve-closing tension in spring 21- is opposed by said roller abutment, and only a very small component of such tension is operative as pressure upon the latch arm 35, so that very little friction exists between the engaging parts 32 and 6 to be overcome by said expansion of the thermostat. i

It will be obvious that when automatic closure of the main valve occurs, gas is thereby also shut off from the auxiliary burner although the local controlling cock 59 remains open. WVhen the control lever 19 is displaced from its position in Fig. 3, however, the cook 59 is at once closed, so it is clear that only in the position of parts shown in .Fig. 4, is gas supplied to the auxiliary burner. In some forms of the inventioml prefer to arrange the cook 59 with resilient means always tending to close the same.

It will be evident that'the burner and heater parts extending upwardly and exterior of the mechanisincasing in the form thereof shown in Figs. 1 to 4-, inclusive, may to advantage be partially or wholly encased to protect the same from drafty conditions and to otherwise conservate the heat. The interval of time constituting the delay before automatic valve closure may be readily varied by altering the amount of engage ment between the part 32 and the part 6, by adding or detracting from the heat radiating propensities of the heat conductor 53 and of the thermostat itself, by varying the magnitude ofthe auxiliary burner flame; by changing the cross section or material of the heat conductor, or by varying the volumetric contents or expansible properties of the thermostat. I

I may avail myself of the useful advantages possessed by the hereinbefore described valve-operating mechanism, and yet utilize other means for thermally energizing the thermostat than those herein described. For instance, in place of the automatically llO ignited auxiliary gas burner operating to heat the thermostat as herein described I may introduce a small capacity, by-pass water conduit which shall be arranged to accommodate a branch thermo-siphon water circulation from a low point to a higher point in the ordinary domestic water boiler or reservoir, and parallel with the main circulation through the tubes or coils of the gas water-heater. Such by-pa ss may be led at one point thereof into thermal proximity to the thermostat, so that when the water flowing therethrough becomes hot (as will be the case only when the entire volume of water, or a designed part thereof, conrained in the boiler becomes heated) the thermostat will be thermally. and operatively energized to trip the valve retaining detent latch as described; and by providing an arrangement whereby theoutlet from the said low point in the boiler to the said bypass circulation may be made selectively adjustable to different levels in the boiler, it will be obvious that my improved, delayed-closing valve may be arranged automatically to cut oil the gas when any desired proportional amount of the water contained in the boiler has become heated.

The principles of the invention exemplified bythe controlling arrangement herein illustrated are, of course, readily as applicable to valves for controlling the supply of gasfor illuminating burners and for other useful purposes as to the particular formot' water-heater valve herein chosen only to demonstrate those principles3also the novel and compact arrangement of indirectly locking detent and the thermostatic means for tripping the same can be used to advantage for governing the automaticmovement of many other heavily tensioned devices, such as an electric switch, or pneumatic valve.

As many other modifications in detail of construction and in means for thermally energizing the thermostat may, of course, be made within the scope of the principle of my invention, I do not limit such scope to the precise embodiment of the invention herein disclosed but what I claim as new 1. A plural gas burner and controlling valve arrangement embodying, in combination; a main burner; a main valve-for regulating the supply of gas thereto; mechanism adapted automatically to actuate said valve; a thermostat arranged to govern the automatic actuation of said valve by said mechanism; an auxiliary burner for operatively energizing said thermostat; an auxiliary conduit arranged to conduct gas from said main valve to said auxiliary burner; an auxiliary valve operating in said auxiliary conduit for regulating the supply of gas to said auxiliary burner; together with common control means operating both said main valve, arrangement embodying, in-combina tion; a main burner; a main valve for regulating the supply of. gas thereto; ;mechanism adapted automatically to actuate said valve; a thermostat arranged to govern the automatic actuation of said valve by said mechanism; an auxiliary, burner foroperatively energizing said thermostat; an auxiliary conduit arranged to conduct gas from said main valve tosaid auxiliary burner; an auxiliary valve operating in said auxiliary conduitfor regulating the supply of gas to said auxiliary burner; together with a controlling member mounted forlimited movement and adapted to engage with operating extensions on each of said main and said auxiliary valves for controlling in predetermined-relation the supply of gas to each of said burners.

3. A plural gas burner and controlling valvearrangement embodying in combination, a main burner; a main valve forv regulating the supply of gasthereto; mechanism adapted automatically to actuate said valve; a thermostat arranged to govern the automatic actuation of said valve bysaid mechanism; an auxiliary burner, for operatively en- GlglZlIlg said thermostat; an auxiliary conduit arranged to conduct gas from said main valve to said auxiliary burner; an auxiliary valve operating in said auxiliary conduit for regulating the supply of gas to said auxiliary burner; together with acontrolling member mounted for limited movement and adapted to engage with operating extensions on each of said main and said ergizing said thermostat; anau-xiliary conduit arrangedto conduct gas from-said main valve to said auxiliary burner; an'auxiliary valve operating in said auxiliary conduit for regulating the supply of gas to saidauxiliary burner; together witha controlling member mounted for limited movement and adapted to engage with operating extensions on each of said main and said auxiliary valves for controlling in' predetermined re-' lation the supplyo-f gas to each of said burners; said member havlng constant operative CIT connection to said main valve and being movable into and out of actuating engagement with said auxiliary valve.

5. A plural gas burner and controlling valve arrangement embodying, in combination; a main burner; a main valve for regulating the supply of gas thereto; mechanism adapted automatically to actuate said valve; a thermostat arranged to govern the automatic actuation of said valve by said mechanism; an auxiliary burner for operatively energizing said thermostat; an auxiliary conduit arranged to conduct gas from said main valve to said auxiliary burner; an auxiliary valve operating in said conduit for regulating thesupply of gas to said auxilia-ry burner; together with a controlling lating the supply of gas thereto; mechanism adapted automatically to actuate-said valve; a thermostat arranged to govern the automatic actuation of said valve by said mechanism; an auxiliary burner for oper'atively energizing said thermostat; an auxiliary conduit arranged to conduct gas frOmsa-id main valve to said auxiliary burner; anauxiliary valve operating in said auxiliary conduit for-regulating the supply of gas: tosaid auxiliary burner; together with a controlling member mounted for limited movement and adapted to engage with operating extensions on each of said main and said auxiliary valves for controllingin predetermined relation the supply of gas to eachburner, said member further having resilient connection with the main valve to tension same for movement and being arranged by a single actuation thereof to energize said resilient connection and toopen said separate valve.

7 A plural gas burner and controlling valve arrangement embodying, in combination; a main burner; a main valve for regulating the supply of gas thereto; mechanism adapted automatically to actuate said valve; a thermostat arranged to govern the automatic actuation of said valve by said mecha nism; an auxiliary burner for operatively energizing said thermostat; an auxiliary conduit arranged to conduct gas from said main valve to said auxiliary burner; an auxiliary valve operating in said conduit for regulating the supply of gas to said auxiliary burner; together with common control means for 'co-op'er'atively and simultaneously ad-- operable means for operating the same; re-v silient means to tension said master valve for automatic closure; a detent and controlling thermostat therefor to govern said automatic closure; a norm-ally inactive burner arranged in heating relation to said thermostat; an igniting arrangement for said burner; and an auxiliary valve structurally separate from said master valve and arranged to govern the supplyof gas from said master valve to said burner,--said auxiliary valve being operablyrelated to said means and arranged to be so governed thereby that gas is delivered to said auxiliary burner only when said master valve is tensioned for closure.

9. A plural valve structure embodying in combination; a master valve arranged to control both a main and an auxiliary supply of gas; manually operable means for operating said master valve; resilient means to tension said master valve for automatic closure; a detent and controlling thermostat therefor to govern said automatic closure; a normally inactive burner arranged in heating relation to said thermostat and receptive to said auxiliary supply of gas, and an auxiliary valve structurally separate from said master valve and ar ranged to govern said auxiliary supply'of gas,-said auxiliary valve being .operably related to said means and operatively gov- 'erned thereby.

10. The combination with a thermostatically governed tension-actuated, rotary device of an extension carried by said device for rotating the'saine; a strut arm pivoted to said extension and yieldingly held to protrude therefromin-definite radial position; a stationary, roller abutment positioned to be wiped by a portion ofsaid arm thereby tocause the latter to. yield fromvits normal position when passing said abutment; and a thermostat and detent controlled thereby normally arranged to engage with said strut arm while the latter is in contact with said abutment, whereby said strut arm is restrained from yielding-and the said device thereby detained.

11. Detent mechanism forholding and releasing a device that is heavily tensioned to rotate about its axis embodying, in combination; an interceptive arm mounted onsaid device for limited swinging movement about,

said arm to prevent the retractive swinging thereof when encountered by said abutment.

12. Detent mechanism for holding from rotative movement, and for permitting release of, a device that is heavily tensioned to turn about its axis embodying in combination; an interceptive arm pivoted on said device in a position normally to protrude a definite extent therefrom; a spring connecting said arm to said device to swing the former to its normal protruding position relative to the latter; an abutment positioned to intercept a portion of said arm thereby to check rotative movement of said device when the arm occupies its said normal protruding position ;said abutment also being arranged to cause said arm to swing retractively about its pivot on said device to permit escapement of the latter; and control means movable to and from a position to prevent the abutment-caused retractive swinging oi said arm relative to said device for governing escapement of the latter.

13. The combination with an oscillatory device of an extension carried by said device for oscillating the same; a pivoted radial arm arranged to turn said device in one direction of its swing through abutting engagement with said extension; resilient connections for tensioning said device toturn in the opposite direction; an independently mounted detent pivoted for movement to and from a position to engage with said device to restrain the latter from turning in said opposite direction; and a trip lever mounted on said arm in a manner to be movable relative thereto and adapted when so moved to displace said detent from its said position, to prevent restraint of th device by said detent.

14. The combination with an oscillatory device of an extension carried by said device for rotatively driving the same; a pivoted radial arm arranged to turn said device in one direction of its swinging movement through abutting engagement with said extension, and arranged to be separable from engagement with said extension in the opposite direction of its swinging movement; a tensioned spring connecting said device and said arm to hold the latter in its said abutting engagement with said extension; a detent pivoted for movement to and from a position to engage with'sa id device thereby to. restrain the latter from following up said arm when the latter is separated from said extension against the tension in said connecting spring; and a combined trip and latch lever mounted on said arm in a manner to move between a position to loci; said arm in a position to tension said device for follow-up movement and a position to free said device from restraint-by said detent 'to permit said follow-up movement.

, 15 In an apparatus employing a common operating handle fordirectly actuating a controlled device and for tensi'cning the same for automatic movement, in comb'ii'iation;

with said handle and saiddevice; a movable detent mounted independently of said device; means of engagementbetween said dc L 1 w tent and said crev ce whereby the iormer holds the latter to prevent its said automatic '5 movement; and a trigger carried by saidrcontrolhandle and arranged thereon normally out'ot operative connection with said means of engagement butadapted upon'separate manipulation and by designedmovement relative to said device, toactuate said-means for freeing the device from restraint by said detent. V,

16. In'an apparatus employing a common operating arm for directly actuating a con trolled device and for tensioning the same for automatic movement, in combination wth said handle and said device; an independently mounted detent; means of engagement between said detent and said device whereby the former holds the latter to prevent the said automatic movement thereof; a second detent for holding said control handle in a position to tension said device for automatic movement; and a trigger carried by said operating armnormally out of operative relation to said means of engagement, but adapted upon separate manipulation and designed movement relative to said device to free both said operating arm and said device from engagement by their re spectively restraining detents. Y

17. Thermo dynamic, latch retracting means embodying in combination a thermostat comprising a shallow chamber formed by two annularly corrugated discs joined at their periphery and containing a thermally expansible fluid; a fiat star=shaped reentorcing plate conforming to each face of saidthermostat, with clips straddling the periphery of said discs for retaining said plates; a central, threaded portion on one of said star plates for mounting the thermostat; and a latch-carrying shaft journaled in opposite the said star plate, and formed between its journaled ends as a crank, arranged at the point of greatest eccentricity thereof,

to bear upon the center of the other star plate; together with resilient means for guxtaposition to the face of said thermostat inaintainingisaid shaft in contact with the said other star plate as described.

18. A thermostatically governed, delayed closing gas valve; embodying in combination; a valve stem adapted for oscillatory rotation between valve-opening and valveclosing positions thereof; an oscillator radial, lever for operating said stem, pivoted thereon, and also adapted for limited swinging movement between valve closing and valve opening positions; a resilient connection between said lever and said stem whereby the former is normally maintained in positive engagement with the latter in the direction of rotation for opening the valve but separable from such engagement in the opposite direction of rotation, and against the tension in said resilient connection; a strut arm pivoted to an extension of said stem and yieldingly held to protrude therefrom; a stationary roller abutment positioned to be engaged by said strut arm in a valve opening position of said stem and to cause the yielding thereof when said arm is passing said abutment in valve-closing movement of said stem; a detent to engage with said strut arm whereby said stem is intercepted in its said valve-closing movement; and a thermostat adapted when heated to trip said detent to cause the latter to yield "from its normal position when passing said abutment; and a controlling detent mechanism normally ar-i ranged to engage with said strut arm while the latter is in contact with said abutment, whereby said strut arm is restrained from yielding and the said device thereby detained.

day of April, l917.

RAYMOND D. SMITH.

W'itnesses: v

JAMES D. GonnoN, E. LILLIAN MGFADDEN.

Signed at Boston Massachusetts, this26th 

